Method of treating bone black or char



' Nav. 2o, lsza 1,692,745-

w. w. KEMP un'rHoD or TREATING BONE BLACK onv can Filed Oct. 28, 1924 2 Sheets-Sheet 1 Nov. 20, 1928.

w. w, KEMP mamon oF HEATING BONE BLACK on CHAR 2 sheets-sheet 2 Filed Oct. 28, 1924 Illa/vill' :Jn/wanton MI//Y//am Wa//ace v/1em/n,

a@ www awww Patented Nov. 20, 1928.r

UNITED STATES" WILLIAM WALLACE KEMP, or BALTIMORE, MARYLAND.

METHOD TBEATING BONE BLACK R CHAR.

Application med october 28, 1924. seri-aint. 746,321.

The present invention relates to a new and improved method of treating bone black or char.

It is known that new black contains ammonia salts to a considerable amount, which salts, unless removed, are detrimental to the color ot liquors iltered through the char, and it is customary to thoroughly wash and burn new char prior to its use in filtration.

used, it is necessary to revivify it by subjecting it to firing in retorts to decompose certain carbonates and carbonize organic matter which cannot be eliminated by washing. It has been proposed to burn away the vegetable carbon, and to decompose carbonates to oxides, by placing the char which is to be reviviied 1n a decarbonizer, that is, a retort, and by external firing of such retort, revivify the char. In some instances, kilns have been used with pipe retorts, through which the char is passed, such retorts being heated to a dull red by external firing.

This type of kiln and"retort is not only expensive to build, but, in the application of the external fire to give the he t necessary to revivification of the char wit in the retort, the apparatus is subjected to such a high temperature. that it soon becomes distorted and 3o burned, and frequent renewals are necessary.

My method ot' revivification, and also for .fthe treatment of new char eliminates entirely the external firing which has been heretofore lustrated in the drawings accompanying this case, it is prcposed to internally fire theretort and subject the char to be revivied to a temperature sufficiently high to free the gasem-f: constituents or impurities and leave the cleansed and revivified char in. the retort. This internal tiring 1s accomplished ,in the absence of suiicient air to support combustion, either of the volatile products, or the material treat-rent, srl-,ifa the, time, the heat generated is sutliciently high to accomplish the result aimed at, the heat It is known also that after' char has been being generated by the flame of aself-sustalnmg mixture introduced into the retort. As a result of this method, the revivifying of the char is eiectively carried out, but since there is insuicient'air in the retort to support combustion, either of the liberated gases, or of the material 1n the retort, all danger of'.

burning of the material or gases, or explosion of these gases, is eliminated.

As stated, in order to effectively accomplish this, propose to subject the material to be revlvified to the flame or the heat of a selfsustained fuel mixture, preferably gaseous, which mixture will sustain combustion in the absence of air sufficiently to treat the material,

but which will not cause any burning of the liberated gases or the material under treatment, since there is not suicient air to support combustion.

In order that the invention may be clearly understood by those skilled in the art, I have shown, in the accompanying drawings, embodlments ot m 1nvention,but'it will be understood that t isdisclosure is merelyillustrative, and in no sense restrictive of the invention, as it may be carried out by the use of other expedients and apparatus.

In the drawings F ig. l is a view in elevation of a reduction apparatus.

Fig. 2 is a view in section of the apparatus shown in-Fig. 1. l l

Fig. 3 is a view of an apparatus similar to 'that shown in Figs. 1 and 2, with certain additions and auxiliary appliances applied thereto. i

Fig. 4 is a view in longitudinal section of another form of continuous apparatus, and

Fig. 5 is a cross sectional view of substantially the line 5--5 of Fig. 4 .looking in the direction of the arrows.

Referring to the drawings by numbers, like numbers indicating like parts in the several views, l() indicates the revivifying chamber, which ma.v be of any approved form, but is preferab y, as shown, in the form of a cylinder which may be rotated in any suitable manner, and is provided with a. suitable filling opening having the door or closnre l1. TheA receptacle 10 may be lined, if

desired, with refractory material, as "conventionally illustrated, and may be mounted for rotation as may be desired, and any convenient means for driving it may be provided.

At one end of the rectpacle 10 is provided itfitarxe a-stuffing box 12 through which passes an inlet pipe 13 for the fuel, preferably gaseous.

At the opposite end of the container is provided a similar stuffing box 14 through which 5 delivers the outlet pipe 15 for the volatile products driven off' from the char 16, conventionally illustrated, as well as the ases of combustion from the internal firing ame.

Preferably the delivery pipe 15 will have the lo upwardly turned neck 17 within the container 10 to receive the gases rising from the material 16 to the upper part of the chamber.

The exclusion of air from the container 10 so as to prevent actual combustion of the l5 material, or liberated gases, and maintain a true distilling action is insured by providing a closed container, such as the container 10, and by maintainin within thatcontainer a pressure from the in et pipe 13 through which the self sustaining mixture passes sufficiently to prevent the entrance of air under atmos pheric preure through any openings or joints in the container.

Preferably, the container 10 will be made as air tight as practicable, but it will be understood that it need not be absolutely sealed from atmosphere because the action of the internal pressure, above referred to, insures the exclusion of atmospheric air from the con- $0 tainer.

I accomplish the revivification of thechar 16, however, by internal firing, Without any da r of burning of the volatile products, bynzlivering throught-he pipe 13 a fuel,

l which is preferably gaseous, andof a selfsustaining character, so that it will burn in the air-tight container, the jet of burning fuel bein conventionally illustrated at 18 in Fig.

2. 'he fuel delivered through the pipe 13 4o is a mixture of gas and air so regulated as to proportion that it will burn in a confined space, there being just sufficient air to support combustion of the fuel, but insufficient to cause ignition and burning of the char 16 or any of the volatile products of the material, and the gaseous constituents, as they are liberated, accumulate in the container 10 and are drawn off' through the neck 17 and the delivery pipe 15.

lo ,The air and as of the gaseous mixture supplied to the urner and which has been herein referred to as a self-sustaining mixture, because it does not contain oxygen in excess of that required to effect combustion of the mixture and not sufficient to effect combustion of the char or gases evolved therefrom during the revivifcation, are thorouvhly premixed outside the retort. For this purpose, any suitable means may be emw ployed. Anapparatus which is the preparation of such a self-sustaining mixture isillustrated and described in patent to Kemp and Van Horn, No. 1,420,658 dated June 27, 1922. The elements of the l gaseous mixture are thoroughly premixed be.

adapted for f fore, being admitted to the burner or pipe leading thereto and thereby anv stratification of the gas and air portions which might introcluce into the container sufficient free oxygen to effect any combustion of the char being treated or of gases evolved therefrom is avoided.

In operation, the c linder or retort 10 will receive its load o char which is to be revivified, the jet 18 will be ignited, the door 11 closed, and the retort 10 will then be revolved to agitate the material 16 and bringI fresh material ,into the zone of act-ion of thel flame.

In the form of the invention shown in Fig.

"3, the cylinder 19 will be construed 'as in the form shown in Figs. 1 and 2, butin order that a continuous feed of material through .the retort may be secured, I incline this retort 19, as shown, and at the upper feeding end of the retort 19 I provide a feed hopper 20" passing through a stuffing box 21 in the tort, with the jet pipe 22 for the self-sustaining mixture traversin the feed pipe of the hopper 20 as shown. 'lghe hopper 20 may, if desired, be provided with a cover and any suitable valved feed trap (not shown) at its upper end so that material may be fedfto the ho per and thence tinuous y.

At the lower or delivery end of the retort 19 a. delivery pipe 23,to receive the revivified char, will be provided, this pipe delivering thro h any suitable receptacle and having cut-d entrance of any considerable volume of air to the retort from that end. A suitable stuffing box 24 will surround the pipev 23, and the gas delivery pipe 25 havi the receivinr neck 26 within the retort 19 :ill be provided With this apparatus a continuous operation may be carried on, it-being understood that the internal firing andthe revivification of the char is the same as described in connection with Figs. 1 and 2, but a continuous operation is effected b proper feeding through the hopper 20 of t char passing ont through the vpipe 23 as the retort is rotated.

I have found it referable, or at least desirable, to delivert e self-sustaining fuel, as conventionally illustrated at 18, under a pressure 'which will not-.blow the flame too far from the pipe '13 so that danger of drivin the flame into the smothering atmosphere of the container and extinginshin yitv will be avoided, and it will remain adJacent the point of exit from the pipe so as to insure proper ignition and burning of the self-sustaining ue Y 'Y 'By this means also any possibility of particles of the material being treated or the gases evolved therefrom being drawn into the stream of fuel prior to its being ignited, is entirely avoided. u

to the retort cons (not shown) to prevent e material, the cleansed lOl) l Uf) Following this method andutilizing apparatus capable of performing it, I am able to revivify char by internal firing very effectively and rapidly, and do away with the somewhat cumbersome methods now in use of tiring the retorts externally. Furthermore, under thismethod and with this apparatus, there is great economy in the matter of fuel, for the application of the revivifying temperature being internal and directly supplied to the material under treatment, there is no loss of heat as in external tiring. Additionally, the initial cost and the cost of maintainance of apparatus necessary to carry out my method is very much reduced over the cost` of apparatus used in external firing'methods.

In Figures 4 and 5 is shown an apparatus generally similar to that form of apparatus shown in Figure 3. v

The inclined container 27 may be of any suitable length, and, as shown, may be made up in sections suitably joined at 28 so that containers of different lengths may be readily made up. The container 27 will be lined with refractory and insulating material, fol# lowing any well known practices.

At one end, preferably the upper inclined end, suitable apparatus for feeding material to the container is provided, the apparatus here shown comprising a feed inlet 29 communicating with a pipe v30 coming from any suitable hopper' or other source of supply. The material may be mechanically advanced through the inlet 29 by suitable means, such as a screw feedl suitably driven, as from the drive pulley 32.

The gas outlet may conveniently be formed by providing the outlet pipe 33 surrounding the inlet 29 and passing through a stuffing box 34 in the head of the container 27, any suitable lead off pipe. 35 for the volatilized constituents being provided.

From this it will be seen that the material can be fed in a continuous stream into the upper end of the container, and will naturally flow down the inclined container to the lower or delivery end. The volatilized products will naturally tend to rise and flow to the upper end of the inclined container, and will pass out through the outlet pipe 33 and lead ofi' pipe 35.

In the form of the invention here shown, I provide the burner 36 at the lower' end of the inclined container so that it will deliver the .self-sustaining flame against the incoming material, said burner 36 being preferably suitably insulated, as by water jacketing or other appropriate means to protect it from heat.

Preferably, the burner 36 will be mounted, as shown, upon the outlet pipe 37, through which the reduced materials may pass. The burner vpipe 36 will enter the outlet pipe 37 through the stuing box 3S, and, at its forward end, will pass through an opening in the vspout of the outlet pipe, projecting slightly be ond, as shown in Figure'f.

he outlet pipe 37 may takew numerous forms, butthe one shown iswell suitedor the purposes of delivering the material. As shown, such outlet pipe is substantially L- shaped, with one limb projectingthrough a stuffing box 39 in the lower head of the inclined container and having an opening 40 4in 'its upper wall to receive the material. The material will be delivered to the opening or mouth 40 of the outlet pipe 37 by means of the wings or flights 41'on the inside of the container 27, which, as the container is revolved, will pick up charges of the material and deliver them to the mouth 40 of the outlet flight. The material will then flow by gravity 'down the inclined pipe 37 and be delivered through the vertical leg 42 to any suitable point of delivery.

It will be understood that the container 27 is so mounted that it may be revolved relative to the inlet and the outlet members hereinbefore described. As the mounting and rotation of such apparatus will be in accordance with any well known practices, it is not thought necessary to detail any particular Way of mounting the container 27 for rotation about its longitudinal axis or means for effecting such rotation.

While I have shown a particular apparatus for carrying out my invention and have described particular steps for practicing it, it will be understood that such variations as are merly the work of the skilled mechanic may still be made without departing from the range of my invention. l

l. The method of revivifying char, which ,l

consists in enclosing the char in a container, 'burning within the container a gaseous body homogeneously premixed outside the container and composed of fuel gas and air, the

proportion of air not exceeding that required to furnish oxygen'necessary to e'ect combustion of the gas, while excluding other air from the container, and discharging from the container the products of combustion and vapors and gases released by the treatment.

2. The method of revivifying char, which .consists in enclosing the char in a container,

burning within the container a homogeneous mixture of fuel gas and air produced exteriorly of the container, the amount of airin such mixture not exceeding that required to furnish the oxygen necessary to effect combustion of the fuel gas, while excluding other air from the container, agitating the char, and discharging from the container the products of combustion and vapors and gases re- -leased by the treatment.

3. The method of revivifying char, which consists in enclosing the char in a container, provided with an outlet for the products of combustion and vapors and gases released iio by the. treatment, and burning within the con` tainer a gaseous body composed of fuel gas and air, the amount of air in such mixture not exceeding that required to furnish the oxygen necessary to effect the combustion of the fuel gas, while excluding other air from the container, the iame of the burning mixture being maintained close to the inlet therefor.

4. The method of revivifying carbonaceous material by heat, which consists inpassing the `material in a substantially continuous streamfthrou h a container provided with an outlet for t e products of combustion and vapors and gases released by the treatment, and subjecting the material to the heat of a self lsustaining burning mixture injected into the container independent of the stream of material being treated, while excluding fr om the container air other than that in said mlxture.

5. The method of evivifying carbonaceous material by heat, which consists in passing the material, in asubstantially continuous stream, through a container having an outlet for the products of combust'on and vapors and gases released by the treatment, and subjecting the material to the heat of a llame of a self-sustaining sisting of a thoroughly pre-mixed gas and air mlxture injected into a container so that exchange of heat is effected according to the principle of countercurrent heat flow, while excluding from the container air other than that contained inthe said mixture.

In testimony whereof Ihave hereunto set my hand.

WILLIAM WALLACE KEMP.

burning mixture con- 

